Effects of Learning on Neural Representations of Rhythm and Beat
Co-Authors:Jessica A Grahn
Virtual or In-person:In-person
Listening to rhythmic sounds elicits activity in the basal ganglia, cerebellum, and motor cortices, including supplementary motor area and premotor cortex. Rhythms with musical structure that give rise to a steady underlying pulse, or 'beat', elicit increased activity in the SMA and basal ganglia, suggesting these areas are involved in beat perception. However, because people hear music regularly, rhythms eliciting a strong beat are necessarily more predictable than amusical, irregularly-timed rhythms that are often used as control stimuli. Thus, neural correlates of beat perception may be confounded by the relative experience-driven predictability of strong-beat rhythms. To address this confound, we will equalize the predictability of a subset of rhythms that vary in beat strength, and measure BOLD activity associated with the rhythms before and after predictability is equalized. Across 4 sessions, participants train on 12 unique rhythms (4 strong-beat, 4 weak-beat, and 4 non-beat) in finger-tapping tasks. In pre- and post-training fMRI sessions, we measure BOLD responses while participants listen to the rhythms during a rhythm discrimination task. Brain regions that are truly sensitive to the beat will maintain activity differences between beat strength conditions in both pre- and post-training scans. However, predictability-sensitive regions will show no difference between beat strength conditions in the post-training scan only, as all rhythms will be equally predictable. Expected results presented alongside previously collected data.